نتایج جستجو برای: fatty esters
تعداد نتایج: 147696 فیلتر نتایج به سال:
Introduction The fatty acid esters synthesis by transesterification of oils to produce biodiesel commonly involves methanol or ethanol as acyl acceptor. The transesterification of vegetable oils catalyzed by lipases is an alternative process for obtaining biodiesel. These biocatalysts working under mild conditions of temperature, allow for easy recovery of glycerol, synthesis of specific alkyl ...
Studies on the synthesis of esters of natural origin fatty acids (oleic acid) and a branched synthetic isostearic acid derived from oleic acid with commercially available selected higher polyols in the presence of homogeneous metallic catalysts have been carried out. The effects of the synthesis temperature, molar ratio and the catalysts amount have also been studied. It was shown that higher f...
The cuticular surface lipids of the red harvester ant, Pogonomyrmex barbatus, were found to contain minor amounts of novel wax esters, in addition to the major components, hydrocarbons. The wax esters ranged in carbon number from C19 to C31 and consisted of esters of both odd- and even-numbered alcohols and acids. Each wax ester with a given carbon number eluted at several different retention t...
The recovery from rat and rabbit tissues of fed methyl-(14)C and ethyl-2-(14)C 2-methylpalmitate with unaltered specific activity has demonstrated the existence of mechanisms for the absorption and deposition of both methyl and ethyl esters of fatty acids, at least for 2-methylpalmitate. In thoracic duct-cannulated rats, approximately 9% of the fed compounds was recovered from the lymph during ...
Because vitamin A in milk is largely present as esterified retinol while blood plasma predominantly contains unesterified retinol, experiments were conducted to determine whether membranes from the lactating mammary gland are able to synthesize retinyl esters in vitro. When microsomes from rats lactating for 7 to 14 days were incubated with [(3)H]retinol dispersed in dimethylsulfoxide, some [(3...
tea leaves contain unsaturated fatty acids, key precursors of volatile compounds contributing to tea aroma quality. tea is cultivated in areas with diverse environmental conditions. nitrogenous fertilizers influence tea yields and quality. a previous single site study demonstrated that increasing nitrogenous fertilizer rates raised fatty acid levels. however it is not known if the magnitudes an...
Fatty acid ethyl esters are secondary metabolites that are produced during microbial fermentation, in fruiting plants and in higher organisms during ethanol stress. In particular, volatile medium-chain fatty acid ethyl esters are important flavour compounds that impart desirable fruit aromas to fermented beverages, including beer and wine. The biochemical synthesis of medium-chain fatty acid et...
Microalgae oil serves as a feedstock for a biorefinery approach to mid-chain (di-)carboxylic acid esters, currently only accessible via demanding synthetic routes. Via the butenolysis of monoand poly-unsaturated fatty acids, short-chain unsaturated fatty acid methyl esters and monoand di-enes were produced in a high selectivity. These olefins were further processed into value added linear mid-c...
Composition of Loureiro and Alvarinho wines from the Vinhos Verdes region, respecting free volatile compounds as well as glycosidically bound aroma precursors, was exhaustively determined by GC-MS after adsorption on XAD-2 resin. On the whole, were identified and quantified 120 volatile compounds in the free fraction and 77 glycosidically bound compounds, belonging to C6-compounds, alcohols, fa...
Fatty acid esters have been synthesized in good yield by reaction between copper(I) ate complexes formed from methylcopper(I) and primary or secondary Grignard reagents and esters of primary iodoalkylcarboxylic acids. The synthetic method is i l lustrated with proced.ures for CHr:gH(CHz)rgCO2C2H5, CeHsCHzO(CH2)16COzCzHs, CH3(CH2)25CO2C2H5, CH3O2C(CH)I2CO2CHI, CzHsOzC(CHz)szCO2C2H5, and CHg(CH2)...
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